Go Back  Offshoreonly.com > Technical > General Q & A
Cam and valvetrain longevity....??? low duration high lift... >

Cam and valvetrain longevity....??? low duration high lift...

Notices

Cam and valvetrain longevity....??? low duration high lift...

Old 09-15-2016, 09:44 PM
  #21  
Registered
iTrader: (3)
 
Join Date: Apr 2006
Location: Toledo Oh
Posts: 9,661
Received 27 Likes on 16 Posts
Default

The answer to all the cam problems and controversy.....


[ATTACH=CONFIG]559443[/ATTACH]
Attached Thumbnails Cam and valvetrain longevity....??? low duration high lift...-10399953_10153601992602399_3818963526569208812_n.jpg  
phragle is offline  
Old 09-15-2016, 09:52 PM
  #22  
Registered
iTrader: (3)
 
Join Date: Oct 2007
Location: yorkville,il
Posts: 8,401
Received 4 Likes on 3 Posts
Default

and their are still some people that think you can spin a hyd roller cam to 6000+rpm with 140 on the seat&under450 on the nose,then they blame the cam or the lifter when things get beat to failure.
mike tkach is offline  
Old 09-15-2016, 10:13 PM
  #23  
Platinum Member
Platinum Member
iTrader: (7)
 
getrdunn's Avatar
 
Join Date: Feb 2009
Location: NW Michigan
Posts: 6,099
Received 1 Like on 1 Post
Default

Originally Posted by SB View Post
Yikes if HR rollers lifters. Or are you saying solid roller lifters ?
Solid roller lifters on billet hyd roller cam. Works well.
getrdunn is offline  
Old 09-15-2016, 10:32 PM
  #24  
Registered
 
Join Date: Oct 2013
Location: rock Island wa
Posts: 1,964
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by SB View Post
Do I dare say us too ?
I only said what many think in the other thread, don't get me wrong, I want every guy to get the most bang for his buck$ and truly feel bad for Tim .
buck35 is offline  
Old 09-15-2016, 10:34 PM
  #25  
Registered
iTrader: (3)
 
Join Date: Jul 2004
Location: chicago
Posts: 11,305
Received 0 Likes on 0 Posts
Default

Originally Posted by getrdunn View Post
Solid roller lifters on billet hyd roller cam. Works well.
Some guys do it the other way too. Run a hydraulic roller on a solid "tight lash" camshaft.

I've noticed some cam cards from custom cam guys, where the lash settings were crossed out, and handwritten "HYD" on the cam card. Wonder if they really are running a tight lash solid profile, and dont even know it. A "cheater" cam so to speak.
MILD THUNDER is offline  
Old 09-15-2016, 10:38 PM
  #26  
Platinum Member
Platinum Member
iTrader: (7)
 
getrdunn's Avatar
 
Join Date: Feb 2009
Location: NW Michigan
Posts: 6,099
Received 1 Like on 1 Post
Default

Originally Posted by Full Force View Post
Mild has a grind that seemed to really wake it up on the computer, the existing numbers were within a few HP of my dyno sheet, I am going to contact a few to get overall opinions, Dean Gellner just did 540's making 706, I am going to talk to him, and Cam Motion direct, and a few others like Comp, Erson and such...

what is your grind? EVERYONE has so fasr told me I need to be in the 250'[email protected] to start..
I worked with dean a couple of times. He loves making power and good at it. He comes up with some pretty good grinds with the help of comp. I wouldn't hesitate to call him. I've got a couple of his grinds myself. My personal opinion and experience on the 250'[email protected] is fine as long as your numbers are what you want at the rpm your running. I know we covered this before as to what is ideal for marine. You spec cam to make peak hp at your max running rpm or spec one that continues to make power 500-750 rpm higher than. If second option makes more power at your max running rpm then for most it would be a no brainier. Good flowing heads with the right size runner don't always like a lot of cam.

I am still shocked what little difference yours was from 5,500-6,000. Gellner was doing a lot of 540's a few years back and getting a solid 650 hp with custom comp grind and dart pro one 310's. Be sure and pm me what you find out from him to make sure it's not the same cam cause I have those numbers. He evidently has something new. Did Bob recommend the 325's? Pm me your ph number if you'd like and I will give you a shout.
getrdunn is offline  
Old 09-15-2016, 10:43 PM
  #27  
Registered
 
Join Date: Oct 2013
Location: rock Island wa
Posts: 1,964
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by dunnitagain View Post
Looks like another Cam thread. What most don't realize is when the lift increases on a Lobe , the Duration also has to increase . Because of Valvetrain Stability. The magic bullet , high lift low duration cams, have a built in flaw . There is not enough Duration on the lobe to control bounce and loft. Everyone thinks that a lifter follows the lobe exactly. Not true. You have what is called Loft , at increasing RPM , the Lifter does not want to follow the lobe . Inertia takes over and objects in motion tend to stay in motion.
Thus the lifter jumps the nose of the lobe , and tries to land gracefully on the backside of the lobe. If it lands to far down the lobe , it bounces. Which sets up a Harmonic through the whole Valvetrain , The only solid points to dampen the Oscillations are , the Lifter and Lobe interface , and the Valve to Seat Interface. Resulting in Valves and Valve Seats that have been beaten to **** , Or Lifters that break due to the severe harmonic ( Bounce ) that is placed on them.
I know the theory , and the brain trust , behind the Magic Bullets. Trust me there is no magic bullet. If a name brand cam company doesnt have the lobe
configuration your looking for, There is a good reason why. That Reason is Thousands of Hours , and Millions of Dollars of R&D into Master Cam Lobe developement. That
actually works .
You obviously have too much common sense. Lol . Not sure if thats legal these days.
buck35 is offline  
Old 09-15-2016, 10:45 PM
  #28  
Registered
iTrader: (5)
 
Join Date: Mar 2008
Location: Traverse City MI
Posts: 3,390
Likes: 0
Received 3 Likes on 2 Posts
Default

Package package package

Leave it alone or improve your entire package , maybe carbs, intakes, exhaust, and Cams....just doing cams Alone won't make you happy.

Good luck and you definitely deserve to be happy with your build.
offshorexcursion is offline  
Old 09-15-2016, 10:46 PM
  #29  
Platinum Member
Platinum Member
iTrader: (7)
 
getrdunn's Avatar
 
Join Date: Feb 2009
Location: NW Michigan
Posts: 6,099
Received 1 Like on 1 Post
Default

Btw I am willing to try a couple on new builds. Help would be nice if anyone is up to it. I'm always up for trying something new. Nothing ventured nothing gained.
getrdunn is offline  
Old 09-15-2016, 10:49 PM
  #30  
Platinum Member
Platinum Member
iTrader: (7)
 
getrdunn's Avatar
 
Join Date: Feb 2009
Location: NW Michigan
Posts: 6,099
Received 1 Like on 1 Post
Default

Bck 548 build loved more intake and carb. 305 cnc heads though

If I recall OP has some clearance issues. Might have to cut some holes. You know.

Be very interesting to put a edelbrock R intake with a 1050 dom

Last edited by getrdunn; 09-15-2016 at 10:56 PM.
getrdunn is offline  

OSO Sponsor
OSO Advertiser
OSO Advertiser

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information

Copyright © 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.

OSO Advertiser